The present invention is directed to a tapper/threader assembly which may be used in connection with a standard lathe having a rotatable chuck and a tail stock positioned over the lathe bed. The assembly may also be used in a drill press, or milling machine.
A prior art combined drill, tap and lathe-center chuck adapter is shown in Norman et al. U.S. Pat. No. 2,714,318. In the Norman patent structure, there is no reciprocal movement between the parts. Therefore, in a Norman tapping operation, the lathe tail stock is being pulled. Because of the mass of the tail stock, it is possible to place too much tension on the threads which would tend to damage the threads.